Pensions and Postretirement Benefits Other than Pensions (Components of the Company's Pension-Related Costs) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
UNITED STATES
Service cost	$ 1.7	$ 1.7	$ 5.2	$ 5.3
Interest cost	2.6	2.7	7.7	7.8
Expected return on plan assets	(3.6)	(3.0)	(10.9)	(8.9)
Administrative costs and other	0.5	0.4	1.4	1.2
Prior service costs	0.0	0.0	0.2	0.2
Amortization of plan net actuarial losses	1.1	1.3	3.0	3.6
Net periodic pension benefit cost	2.3	3.1	6.6	9.2
Non-U.S.
Service cost	0.4	0.3	1.4	1.1
Interest cost	2.2	2.1	6.4	6.4
Expected return on plan assets	(3.9)	(3.4)	(11.7)	(10.3)
Administrative costs and other	0.4	0.5	1.2	1.3
Amortization of plan net actuarial losses	0.3	0.4	0.7	1.3
Net periodic pension benefit cost	$ (0.6)	$ (0.1)	$ (2.0)	$ (0.2)